Nonlinear dynamic analysis of base isolated cable-stayed bridge under earthquake excitations

In this paper, it is aimed to determine the earthquake effects on cable-stayed bridge isolated by single concave friction pendulum bearings (SCFP). In this context, Manavgat cable-stayed bridge is selected as a numerical application. The selected bridge has 202 m composite deck and 42 m steel tower. 3D finite element models (FEM) of the base isolated and non-isolated bridge are modeled by using SAP2000. Three different earthquakes which are 11 December 1999 Düzce, 23 November 2011 Van and 13 March 1992 Erzincan earthquakes are subjected to the 3D FEM models in order to determine the seismic behavior of the bridges. BOL-090 and BOL-000; ERCIS-EW and ERCIS-NS; ERZ-NS and ERZ-EW components of ground motions obtained from PEER and AFAD are applied to the bridges at the longitudinal and transverse directions, respectively. Nonlinear time history analysis is executed to determine the dynamic responses of the bridge. Comparison of dynamic behavior of isolated and non-isolated bridge with and without the SCFP bearings under three different earthquake motions has been conducted. The results obtained from analyses of 3D FEM of the bridge are presented by graphics and tables in detail. It is seen that using of isolation system reduces the destructive effects of earthquakes on the bridge.